Robots are electromechanical devices that perform work tasks automatically or autonomously. Robots are used in a host of applications, many of which present unique design challenges. For instance, complex surface-roving robots generally referred to as “rovers” may be used in space exploration missions as well as in Earth-based search and rescue operations. Controlled via remote link, rovers can employ an array of sensors to collect and analyze soil samples, measure the atmospheric composition and weather conditions, and collect high-resolution imagery of the surface terrain over an extended period, often in relatively inhospitable operating environments. NASA's Mars Pathfinder rover Sojourner and the more recent twin Mars Exploration rovers Spirit and Opportunity are examples of some space exploration rovers.
Once deployed on a surface, conventional rovers are typically propelled along a surface. In particularly sandy or loamy soil environments such as the lunar or Martian surfaces, conventional propulsion devices may become fouled and stuck. Rovers may therefore avoid exploring certain terrain features, or they may be programmed to follow a less than optimal route. Likewise, in some Earth-based roving applications, miniature rovers may be used to search through unstable piles of rubble or confined areas that are inaccessible to human search teams. Conventional rover designs may be less than optimal in these applications due to certain design limitations that may cause the rovers to become irretrievably stuck in the rubble or other difficult to navigate surface features.